Abstract:
With the rapid development of China's power grid, the excessive short-circuit current in power systems has become increasingly prominent, seriously affecting the safe operation of system and equipment. In view of the shortcomings of the existing limitation measures for short-circuit current, a short-circuit current limitation method based on the dynamic adjustment of the system topology is proposed in this paper. By quickly changing the system topology during short-circuit faults within a short period, the short-circuit current can be limited, avoiding the impacts on the normal operation of the system caused by the current limitation measures. The system topology adjustment method was studied, the timing coordination and action strategy are proposed. Based on the typical system structures and parameters, the short-circuit current suppression effect and the effects of topology adjustment on system stability and relay protection are analyzed. The key technology of the high-speed switch of the key equipment of this method is preliminarily analyzed.